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mpv/linux/vbelib.c

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/*
This file contains implementation of VESA library which is based on
LRMI (Linux real-mode interface).
So it's not an emulator - it calls real int 10h handler under Linux.
Note: VESA is available only on x86 systems.
You can redistribute this file under terms and conditions
of GNU General Public licence v2.
Written by Nick Kurshev <nickols_k@mail.ru>
*/
#include "vbelib.h"
#include "lrmi.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <sys/io.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <ctype.h>
#include <unistd.h>
#include <fcntl.h>
static struct VesaProtModeInterface vbe_pm_info;
static struct VesaModeInfoBlock curr_mode_info;
static inline int VERR(const void *p)
{
register int retval;
__asm __volatile(
"xorl %0, %0\n\t"
"verr %1\n\t"
"setnz %b0"
:"=r"(retval)
:"m"(*(unsigned char *)p)
:"memory");
return retval;
}
#if 0
static inline int VERW(const void *p)
{
register int retval;
__asm __volatile(
"xorl %0, %0\n\t"
"verw %1\n\t"
"setnz %b0"
:"=r"(retval)
:"m"(*(unsigned char *)p)
:"memory");
return retval;
}
#endif
#define HAVE_VERBOSE_VAR 1
#ifdef HAVE_VERBOSE_VAR
extern int verbose;
static void __dump_regs(struct LRMI_regs *r)
{
printf("vbelib: eax=%08lXh ebx=%08lXh ecx=%08lXh edx=%08lXh\n"
"vbelib: edi=%08lXh esi=%08lXh ebp=%08lXh esp=%08lXh\n"
"vbelib: ds=%04Xh es=%04Xh ss=%04Xh cs:ip=%04X:%04X\n"
"vbelib: fs=%04Xh gs=%04Xh ss:sp=%04X:%04X flags=%04X\n"
,(unsigned long)r->eax,(unsigned long)r->ebx,(unsigned long)r->ecx,(unsigned long)r->edx
,(unsigned long)r->edi,(unsigned long)r->esi,(unsigned long)r->ebp,(unsigned long)r->reserved
,r->ds,r->es,r->ss,r->cs,r->ip
,r->fs,r->gs,r->ss,r->sp,r->flags);
}
static inline int VBE_LRMI_int(int int_no, struct LRMI_regs *r)
{
int retval;
if(verbose > 1)
{
printf("vbelib: registers before int %02X\n",int_no);
__dump_regs(r);
}
retval = LRMI_int(int_no,r);
if(verbose > 1)
{
printf("vbelib: Interrupt handler returns: %X\n",retval);
printf("vbelib: registers after int %02X\n",int_no);
__dump_regs(r);
}
return retval;
}
#else
#define VBE_LRMI_int(int_no,regs) (VBE_LRMI_int(int_no,regs))
#endif
static unsigned hh_int_10_seg;
static int fd_mem;
int vbeInit( void )
{
unsigned short iopl_port;
size_t i;
int retval;
if(!LRMI_init()) return VBE_VM86_FAIL;
/*
Allow read/write to ALL io ports
*/
hh_int_10_seg = *(unsigned short *)PhysToVirtSO(0x0000,0x0042);
/* Video BIOS should be at C000:0000 and above */
hh_int_10_seg >>= 12;
if(hh_int_10_seg < 0xC) return VBE_BROKEN_BIOS;
ioperm(0, 1024, 1);
iopl(3);
memset(&vbe_pm_info,0,sizeof(struct VesaProtModeInterface));
retval = vbeGetProtModeInfo(&vbe_pm_info);
if(retval != VBE_OK) return retval;
i = 0;
while((iopl_port=vbe_pm_info.iopl_ports[i]) != 0xFFFF
&& vbe_pm_info.iopl_ports[i++] > 1023) ioperm(iopl_port,1,1);
iopl(3);
fd_mem = open("/dev/mem",O_RDWR);
return VBE_OK;
}
int vbeDestroy( void )
{
close(fd_mem);
return VBE_OK;
}
/* Fixme!!! This code is compatible only with mplayer's version of lrmi*/
static inline int is_addr_valid(const void *p)
{
return (p < (const void *)0x502) ||
(p >= (const void *)0x10000 && p < (const void *)0x20000) ||
(p >= (const void *)0xa0000 && p < (const void *)0x100000);
}
static int check_str(const unsigned char *str)
{
size_t i;
int null_found = 0;
for(i = 0;i < 256;i++)
{
if(is_addr_valid(&str[i]))
{
if(VERR(&str[i]))
{
if(!str[i]) { null_found = 1; break; }
}
else break;
}
else break;
}
return null_found;
}
static int check_wrd(const unsigned short *str)
{
size_t i;
int ffff_found = 0;
for(i = 0;i < 1024;i++)
{
if(is_addr_valid(&str[i]))
{
if(VERR(&str[i]))
{
if(str[i] == 0xffff) { ffff_found = 1; break; }
}
else break;
}
else break;
}
return ffff_found;
}
static void print_str(unsigned char *str)
{
size_t i;
fflush(stdout);
printf("vbelib: ");
for(i = 0;i < 256;i++) { printf("%02X(%c) ",str[i],isprint(str[i])?str[i]:'.'); if(!str[i]) break; }
printf("\n");
fflush(stdout);
}
static void print_wrd(unsigned short *str)
{
size_t i;
fflush(stdout);
printf("vbelib: ");
for(i = 0;i < 256;i++) { printf("%04X ",str[i]); if(str[i] == 0xffff) break; }
printf("\n");
fflush(stdout);
}
int vbeGetControllerInfo(struct VbeInfoBlock *data)
{
struct LRMI_regs r;
void *rm_space;
int retval;
if(!(rm_space = LRMI_alloc_real(sizeof(struct VbeInfoBlock)))) return VBE_OUT_OF_DOS_MEM;
memcpy(rm_space,data,sizeof(struct VbeInfoBlock));
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f00;
r.es = VirtToPhysSeg(rm_space);
r.edi = VirtToPhysOff(rm_space);
if(!VBE_LRMI_int(0x10,&r))
{
LRMI_free_real(rm_space);
return VBE_VM86_FAIL;
}
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
FarPtr fpdata;
retval = VBE_OK;
memcpy(data,rm_space,sizeof(struct VbeInfoBlock));
fpdata.seg = (unsigned long)(data->OemStringPtr) >> 16;
fpdata.off = (unsigned long)(data->OemStringPtr) & 0xffff;
data->OemStringPtr = PhysToVirt(fpdata);
if(!check_str(data->OemStringPtr)) data->OemStringPtr = NULL;
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1)
{
printf("vbelib: OemStringPtr=%04X:%04X => %p\n",fpdata.seg,fpdata.off,data->OemStringPtr);
if(data->OemStringPtr) print_str(data->OemStringPtr);
fflush(stdout);
}
#endif
fpdata.seg = (unsigned long)(data->VideoModePtr) >> 16;
fpdata.off = (unsigned long)(data->VideoModePtr) & 0xffff;
data->VideoModePtr = PhysToVirt(fpdata);
if(!check_wrd(data->VideoModePtr))
{
data->VideoModePtr = NULL;
retval = VBE_BROKEN_BIOS;
}
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1)
{
printf("vbelib: VideoModePtr=%04X:%04X => %p\n",fpdata.seg,fpdata.off,data->VideoModePtr);
if(data->VideoModePtr) print_wrd(data->VideoModePtr);
fflush(stdout);
}
#endif
fpdata.seg = (unsigned long)(data->OemVendorNamePtr) >> 16;
fpdata.off = (unsigned long)(data->OemVendorNamePtr) & 0xffff;
data->OemVendorNamePtr = PhysToVirt(fpdata);
if(!check_str(data->OemVendorNamePtr)) data->OemVendorNamePtr = NULL;
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1)
{
printf("vbelib: OemVendorNamePtr=%04X:%04X => %p\n",fpdata.seg,fpdata.off,data->OemVendorNamePtr);
if(data->OemVendorNamePtr) print_str(data->OemVendorNamePtr);
fflush(stdout);
}
#endif
fpdata.seg = (unsigned long)(data->OemProductNamePtr) >> 16;
fpdata.off = (unsigned long)(data->OemProductNamePtr) & 0xffff;
data->OemProductNamePtr = PhysToVirt(fpdata);
if(!check_str(data->OemProductNamePtr)) data->OemProductNamePtr = NULL;
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1)
{
printf("vbelib: OemProductNamePtr=%04X:%04X => %p\n",fpdata.seg,fpdata.off,data->OemProductNamePtr);
if(data->OemVendorNamePtr) print_str(data->OemProductNamePtr);
fflush(stdout);
}
#endif
fpdata.seg = (unsigned long)(data->OemProductRevPtr) >> 16;
fpdata.off = (unsigned long)(data->OemProductRevPtr) & 0xffff;
data->OemProductRevPtr = PhysToVirt(fpdata);
if(!check_str(data->OemProductRevPtr)) data->OemProductRevPtr = NULL;
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1)
{
printf("vbelib: OemProductRevPtr=%04X:%04X => %p\n",fpdata.seg,fpdata.off,data->OemProductRevPtr);
if(data->OemProductRevPtr) print_str(data->OemProductRevPtr);
fflush(stdout);
}
#endif
}
return retval;
}
int vbeGetModeInfo(unsigned mode,struct VesaModeInfoBlock *data)
{
struct LRMI_regs r;
void *rm_space;
int retval;
if(!(rm_space = LRMI_alloc_real(sizeof(struct VesaModeInfoBlock)))) return VBE_OUT_OF_DOS_MEM;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f01;
r.ecx = mode;
r.es = VirtToPhysSeg(rm_space);
r.edi = VirtToPhysOff(rm_space);
if(!VBE_LRMI_int(0x10,&r))
{
LRMI_free_real(rm_space);
return VBE_VM86_FAIL;
}
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
retval = VBE_OK;
memcpy(data,rm_space,sizeof(struct VesaModeInfoBlock));
}
return retval;
}
int vbeSetMode(unsigned mode,struct VesaCRTCInfoBlock *data)
{
struct LRMI_regs r;
void *rm_space = NULL;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
if(data)
{
if(!(rm_space = LRMI_alloc_real(sizeof(struct VesaCRTCInfoBlock)))) return VBE_OUT_OF_DOS_MEM;
r.es = VirtToPhysSeg(rm_space);
r.edi = VirtToPhysOff(rm_space);
memcpy(rm_space,data,sizeof(struct VesaCRTCInfoBlock));
}
r.eax = 0x4f02;
r.ebx = mode;
retval = VBE_LRMI_int(0x10,&r);
if(rm_space) LRMI_free_real(rm_space);
if(!retval) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
/* Just info for internal use (currently in SetDiplayStart func). */
vbeGetModeInfo(mode&0x1f,&curr_mode_info);
retval = VBE_OK;
}
return retval;
}
int vbeGetMode(unsigned *mode)
{
struct LRMI_regs r;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f03;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
*mode = r.ebx;
retval = VBE_OK;
}
return retval;
}
int vbeSaveState(void **data)
{
struct LRMI_regs r;
int retval;
void *rm_space;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f04;
r.edx = 0x00;
r.ecx = 0x0f;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval != 0x4f) return retval;
if(!(rm_space = LRMI_alloc_real((r.ebx & 0xffff)*64))) return VBE_OUT_OF_DOS_MEM;
r.eax = 0x4f04;
r.edx = 0x01;
r.ecx = 0x0f;
r.es = VirtToPhysSeg(rm_space);
r.ebx = VirtToPhysOff(rm_space);
if(!VBE_LRMI_int(0x10,&r))
{
LRMI_free_real(rm_space);
return VBE_VM86_FAIL;
}
retval = r.eax & 0xffff;
if(retval != 0x4f)
{
LRMI_free_real(rm_space);
return retval;
}
*data = rm_space;
return VBE_OK;
}
int vbeRestoreState(void *data)
{
struct LRMI_regs r;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f04;
r.edx = 0x02;
r.ecx = 0x0f;
r.es = VirtToPhysSeg(data);
r.ebx = VirtToPhysOff(data);
retval = VBE_LRMI_int(0x10,&r);
LRMI_free_real(data);
if(!retval) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f) retval = VBE_OK;
return retval;
}
int vbeGetWindow(unsigned *win_num)
{
struct LRMI_regs r;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f05;
r.ebx = (*win_num & 0x0f) | 0x0100;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
*win_num = r.edx & 0xffff;
retval = VBE_OK;
}
return retval;
}
int vbeSetWindow(unsigned win_num,unsigned win_gran)
{
int retval;
if(vbe_pm_info.SetWindowCall)
{
/* Don't verbose this stuff from performance reasons */
/* 32-bit function call is much better of int 10h */
__asm __volatile(
"pushl %%ebx\n"
"movl %1, %%ebx\n"
::"a"(0x4f05),"S"(win_num & 0x0f),"d"(win_gran):"memory");
(*vbe_pm_info.SetWindowCall)();
__asm __volatile("popl %%ebx":::"memory");
retval = VBE_OK;
}
else
{
struct LRMI_regs r;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f05;
r.ebx = win_num & 0x0f;
r.edx = win_gran;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f) retval = VBE_OK;
}
return retval;
}
int vbeGetScanLineLength(unsigned *num_pixels,unsigned *num_bytes)
{
struct LRMI_regs r;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f06;
r.ebx = 1;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
if(num_bytes) *num_bytes = r.ebx & 0xffff;
if(num_pixels) *num_pixels= r.ecx & 0xffff;
retval = VBE_OK;
}
return retval;
}
int vbeGetMaxScanLines(unsigned *num_pixels,unsigned *num_bytes, unsigned *num_lines)
{
struct LRMI_regs r;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f06;
r.ebx = 3;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
if(num_bytes) *num_bytes = r.ebx & 0xffff;
if(num_pixels) *num_pixels= r.ecx & 0xffff;
if(num_lines) *num_lines = r.edx & 0xffff;
retval = VBE_OK;
}
return retval;
}
int vbeSetScanLineLength(unsigned num_pixels)
{
int retval;
struct LRMI_regs r;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f06;
r.ebx = 0;
r.ecx = num_pixels;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f) retval = VBE_OK;
return retval;
}
int vbeSetScanLineLengthB(unsigned num_bytes)
{
int retval;
struct LRMI_regs r;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f06;
r.ebx = 2;
r.ecx = num_bytes;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f) retval = VBE_OK;
return retval;
}
int vbeGetDisplayStart(unsigned *pixel_num,unsigned *scan_line)
{
struct LRMI_regs r;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f07;
r.ebx = 1;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
if(pixel_num) *pixel_num = r.ecx & 0xffff;
if(scan_line) *scan_line = r.edx & 0xffff;
retval = VBE_OK;
}
return retval;
}
int vbeSetDisplayStart(unsigned long offset, int vsync)
{
int retval;
if(vbe_pm_info.SetDisplayStart)
{
/* Don't verbose this stuff from performance reasons */
/* 32-bit function call is much better of int 10h */
__asm __volatile(
"pushl %%ebx\n"
"movl %1, %%ebx\n"
::"a"(0x4f07),"S"(vsync ? 0x80 : 0),
"c"((offset>>2) & 0xffff),"d"((offset>>18)&0xffff):"memory");
(*vbe_pm_info.SetDisplayStart)();
__asm __volatile("popl %%ebx":::"memory");
retval = VBE_OK;
}
else
{
#if 0
/* Something wrong here */
struct LRMI_regs r;
unsigned long pixel_num;
memset(&r,0,sizeof(struct LRMI_regs));
pixel_num = offset%(unsigned long)curr_mode_info.BytesPerScanLine;
if(pixel_num*(unsigned long)curr_mode_info.BytesPerScanLine!=offset) pixel_num++;
r.eax = 0x4f07;
r.ebx = vsync ? 0x82 : 2;
r.ecx = pixel_num;
r.edx = offset/(unsigned long)curr_mode_info.BytesPerScanLine;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f) retval = VBE_OK;
#endif
retval = VBE_BROKEN_BIOS;
}
return retval;
}
int vbeSetScheduledDisplayStart(unsigned long offset, int vsync)
{
int retval;
struct LRMI_regs r;
unsigned long pixel_num;
memset(&r,0,sizeof(struct LRMI_regs));
pixel_num = offset%(unsigned long)curr_mode_info.BytesPerScanLine;
if(pixel_num*(unsigned long)curr_mode_info.BytesPerScanLine!=offset) pixel_num++;
r.eax = 0x4f07;
r.ebx = vsync ? 0x82 : 2;
r.ecx = offset;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f) retval = VBE_OK;
return retval;
}
struct realVesaProtModeInterface
{
unsigned short SetWindowCall;
unsigned short SetDisplayStart;
unsigned short SetPaletteData;
unsigned short iopl_ports;
}__attribute__((packed));
int vbeGetProtModeInfo(struct VesaProtModeInterface *pm_info)
{
struct LRMI_regs r;
int retval;
unsigned info_offset;
struct realVesaProtModeInterface *rm_info;
memset(&r,0,sizeof(struct LRMI_regs));
r.eax = 0x4f0a;
r.ebx = 0;
if(!VBE_LRMI_int(0x10,&r)) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f)
{
retval = VBE_OK;
info_offset = r.edi&0xffff;
if((r.es >> 12) != hh_int_10_seg) retval = VBE_BROKEN_BIOS;
rm_info = PhysToVirtSO(r.es,info_offset);
pm_info->SetWindowCall = PhysToVirtSO(r.es,info_offset+rm_info->SetWindowCall);
if(!is_addr_valid(pm_info->SetWindowCall)) retval = VBE_BROKEN_BIOS;
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1) printf("vbelib: SetWindowCall=%04X:%04X => %p\n",r.es,info_offset+rm_info->SetWindowCall,pm_info->SetWindowCall);
#endif
pm_info->SetDisplayStart = PhysToVirtSO(r.es,info_offset+rm_info->SetDisplayStart);
if(!is_addr_valid(pm_info->SetDisplayStart)) retval = VBE_BROKEN_BIOS;
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1) printf("vbelib: SetDisplayStart=%04X:%04X => %p\n",r.es,info_offset+rm_info->SetDisplayStart,pm_info->SetDisplayStart);
#endif
pm_info->SetPaletteData = PhysToVirtSO(r.es,info_offset+rm_info->SetPaletteData);
if(!is_addr_valid(pm_info->SetPaletteData)) retval = VBE_BROKEN_BIOS;
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1) printf("vbelib: SetPaletteData=%04X:%04X => %p\n",r.es,info_offset+rm_info->SetPaletteData,pm_info->SetPaletteData);
#endif
pm_info->iopl_ports = PhysToVirtSO(r.es,info_offset+rm_info->iopl_ports);
if(!check_wrd(pm_info->iopl_ports))
{
pm_info->iopl_ports = NULL;
retval = VBE_BROKEN_BIOS;
}
#ifdef HAVE_VERBOSE_VAR
if(verbose > 1)
{
printf("vbelib: iopl_ports=%04X:%04X => %p\n",r.es,info_offset+rm_info->iopl_ports,pm_info->iopl_ports);
if(pm_info->iopl_ports) print_wrd(pm_info->iopl_ports);
fflush(stdout);
}
#endif
}
return retval;
}
/* --------- Standard VGA stuff -------------- */
int vbeWriteString(int x, int y, int attr, char *str)
{
struct LRMI_regs r;
void *rm_space = NULL;
int retval;
memset(&r,0,sizeof(struct LRMI_regs));
r.ecx = strlen(str);
r.edx = ((y<<8)&0xff00)|(x&0xff);
r.ebx = attr;
if(!(rm_space = LRMI_alloc_real(r.ecx))) return VBE_OUT_OF_DOS_MEM;
r.es = VirtToPhysSeg(rm_space);
r.ebp = VirtToPhysOff(rm_space);
memcpy(rm_space,str,r.ecx);
r.eax = 0x1300;
retval = VBE_LRMI_int(0x10,&r);
if(rm_space) LRMI_free_real(rm_space);
if(!retval) return VBE_VM86_FAIL;
retval = r.eax & 0xffff;
if(retval == 0x4f) retval = VBE_OK;
return retval;
}
void * vbeMapVideoBuffer(unsigned long phys_addr,unsigned long size)
{
void *lfb;
if(fd_mem == -1) return NULL;
if(verbose > 1) printf("vbelib: vbeMapVideoBuffer(%08lX,%08lX)\n",phys_addr,size);
/* Here we don't need with MAP_FIXED and prefered address (first argument) */
lfb = mmap((void *)0,size,PROT_READ | PROT_WRITE,MAP_SHARED,fd_mem,phys_addr);
return lfb == (void *)-1 ? 0 : lfb;
}
void vbeUnmapVideoBuffer(unsigned long linear_addr,unsigned long size)
{
if(verbose > 1) printf("vbelib: vbeUnmapVideoBuffer(%08lX,%08lX)\n",linear_addr,size);
munmap((void *)linear_addr,size);
}
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